The Heel Complex: Anatomy, Imaging, Pathologic Conditions, and Treatment.

The differential diagnosis for heel pain is broad but primarily involves abnormalities of the Achilles tendon, calcaneus, and plantar fascia. Achilles tendon disorders include tendinosis, tendinitis, and partial or complete tears. Tendinosis refers to tendon degeneration, while tendinitis is inflammation after acute overload. Untreated tendinosis can progress to partial or complete tears. Tendon disorders can be accompanied by paratenonitis or inflammation of the loose sheath enclosing the tendon. Initial management involves rehabilitation and image-guided procedures. Operative management is reserved for tendon tears and includes direct repair, tendon transfer, and graft reconstruction. The calcaneus is the most commonly fractured tarsal bone. The majority of fractures are intra-articular; extra-articular fractures, stress or insufficiency fractures, medial process avulsion, and neuropathic avulsion can also occur. Posterosuperior calcaneal exostosis or Haglund deformity, retrocalcaneal bursitis, and insertional Achilles tendinosis form the characteristic triad of Haglund syndrome. It is initially managed with orthotics and physiotherapy. Operative management aims to correct osseous or soft-tissue derangements. The plantar fascia is a strong fibrous tissue that invests the sole of the foot and contributes to midfoot stability. Inflammation or plantar fasciitis is the most common cause of heel pain and can be related to overuse or mechanical causes. Acute rupture is less common but can occur in preexisting plantar fasciitis. Conservative treatment includes footwear modification, calf stretches, and percutaneous procedures. The main operative treatment is plantar fasciotomy. Plantar fibromatosis is a benign fibroblastic proliferation within the fascia that can be locally aggressive and is prone to recurrence. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Ultrasonography in plantar fibromatosis: the conduit between heel pain and 'catwalk'.

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Relationship between dietary characteristics and heel quantitative ultrasound parameters in postmenopausal women from the OsteoLaus cohort.

The role of dietary patterns in the development of osteoporosis is unclear. The heel quantitative ultrasound (QUS) is a potential alternative to Dual X-Ray Absorptiometry. Nutrients, foods, dietary patterns and compliance to dietary guidelines were compared between the lowest and the highest tertiles of QUS parameters [Broadband Ultrasound Attenuation (BUA), Speed of Sound (SOS), Stiffness Index (SI)], using data from the OsteoLaus cohort. Participants in the highest tertiles of QUS parameters (385 for BUA, 397 for SOS, 386 for SI) were younger, of higher body weight, and had less major osteoporotic fractures. Women in the highest tertiles of SI and BUA consumed more fat (35.1 ± 0.4 vs 33.9 ± 0.4 and 34.9 ± 0.4 vs 33.8 ± 0.4 gr/day for SI and BUA, respectively, p < 0.05), and complied less frequently with dairy intake guidelines [odds ratio (95% confidence interval): 0.70 (0.53-0.92) and 0.72 (0.55-0.95) for SI and BUA, respectively, p < 0.05] than women in the lowest tertile. No differences were found regarding dietary patterns, healthy dietary scores, or compliance to dietary guidelines. Postmenopausal women in the highest QUS tertiles were younger, of higher weight and BMI, consumed more monounsaturated fatty acids and less dairy and calcium than women in the lowest tertiles. No differences were found between QUS tertiles regarding dietary patterns.

Heel quantitative ultrasound (QUS) predicts incident fractures independently of trabecular bone score (TBS), bone mineral density (BMD), and FRAX: the OsteoLaus Study.

This study aimed to better define the role of heel-QUS in fracture prediction. Our results showed that heel-QUS predicts fracture independently of FRAX, BMD, and TBS. This corroborates its use as a case finding/pre-screening tool in osteoporosis management. INTRODUCTION: Quantitative ultrasound (QUS) characterizes bone tissue based on the speed of sound (SOS) and broadband ultrasound attenuation (BUA). Heel-QUS predicts osteoporotic fractures independently of clinical risk factors (CRFs) and bone mineral density (BMD). We aimed to investigate whether (1) heel-QUS parameters predict major osteoporotic fractures (MOF) independently of the trabecular bone score (TBS) and (2) the change of heel-QUS parameters over 2.5 years is associated with fracture risk. METHODS: One thousand three hundred forty-five postmenopausal women from the OsteoLaus cohort were followed up for 7 years. Heel-QUS (SOS, BUA, and stiffness index (SI)), DXA (BMD and TBS), and MOF were assessed every 2.5 years. Pearson's correlation and multivariable regression analyses were used to determine associations between QUS and DXA parameters and fracture incidence. RESULTS: During a mean follow-up of 6.7 years, 200 MOF were recorded. Fractured women were older, more treated with anti-osteoporosis medication; had lower QUS, BMD, and TBS; higher FRAX-CRF risk; and more prevalent fractures. TBS was significantly correlated with SOS (0.409) and SI (0.472). A decrease of one SD in SI, BUA or SOS increased the MOF risk by (OR(95%CI)) 1.43 (1.18-1.75), 1.19 (0.99-1.43), and 1.52 (1.26-1.84), respectively, after adjustment for FRAX-CRF, treatment, BMD, and TBS. We found no association between the change of QUS parameters in 2.5 years and incident MOF. CONCLUSION: Heel-QUS predicts fracture independently of FRAX, BMD, and TBS. Thus, QUS represents an important case finding/pre-screening tool in osteoporosis management. The change in QUS over time was not associated with future fractures, making it inappropriate for patient monitoring.

Short-termed changes in quantitative ultrasound estimated bone density among young men in an 18-weeks follow-up during their basic training for the Swiss Armed Forces.

Background: Quantitative Ultrasound (QUS) methods have been widely used to assess estimated bone density. This study aimed to assess changes in estimated bone density in association with changes in body composition, physical activity, and anthropometry. Methods: We examined changes in anthropometry, body composition, and physical activity associated with changes in estimated bone mineral density (measured using quantitative ultrasound with a heel ultrasound device indicating broadband ultrasound attenuation BUA and speed of sound SOS) in a follow-up sample of n = 73 young men at the beginning and again 18 weeks later at the end of basic military training. Results: At the end of the basic training, the subjects were on average significantly heavier (+1.0%), slightly taller (+0.5%) and had a higher fat mass (+6.6%) and grip strength (+8.6%). A significant decrease in mean physical activity (-49.5%) and mean estimated bone density calculated with BUA (-7.5%) was observed in the paired t-test. The results of the multivariable linear regressions (backward selection) show that changes in skeletal muscle mass (delta = 2nd measurement minus 1st measurement) have negative and body weight (delta) have positive association with the speed of sound SOS (delta), while fat mass (delta) and physical activity (delta) had the strongest negative associations with estimated bone mineral density (delta). In particular, we found a negative association between fat mass (delta) and estimated bone mineral density (delta, estimated with BUA). Conclusion: Our study suggests that estimated bone density from the calcaneus can change within a few months even in young and mostly healthy individuals, depending upon physical activity levels and other co-factors. Further studies including other troop types as control groups as well as on women should follow in order to investigate this public health relevant topic in more depth. To what extent the estimated bone density measurement with quantitative ultrasound is clinically relevant needs to be investigated in further studies.

Ultrasonic Evaluation of the Heel Fat Pad Under Loading Conditions Using a Polymethylpentene Resin Plate: Part 2. Reliability and Agreement Study.

Previously, we developed an instrument to evaluate the heel fat pad (HFP) two-layer structure, under varying loading conditions, with ultrasonography from the plantar surface through a polymethylpentene resin plate; the measured values were equivalent to those obtained without this plate. The study described here aimed to determine the intra- and inter-examiner reliabilities of the HFP thickness measurements and the agreement between long- and short-axis measured values using this instrument. Two examiners successively recorded the HFPs of 40 healthy adults twice under the no loading and loading conditions on the long- and short-axis scans. The HFPs were classified into two layers, and their thicknesses were measured. Short-term intra- and inter-examiner reliabilities were determined using the intraclass correlation coefficients. Measurements were repeated 1 mo later to determine the long-term intra-examiner reliability. The agreement between the measured long- and short-axis values was investigated by calculating the minimal detectable changes. The determined short- and long-term intra-examiner reliabilities ranged from 0.750 to 0.999 and from 0.765 to 0.952, respectively. Inter-examiner reliability ranged from 0.765 to 0.997. Differences may occur between the values measured at different axes. The measurements using this evaluation instrument were reliable, and it is best to unify the measurement axis for quantitative research.

[Platelet-rich plasma as a therapeutic option in heel fat pad syndrome]. / Plasma rico en plaquetas como opción terapéutica en el síndrome de la almohadilla grasa plantar.

Heel fat pad syndrome is the second most frequent cause of heel pain at Rehabilitation services. It is a structure damage of the plantar fat that leads to loss of cushioning in gait and plantar pain. It is due to degeneration or repeated trauma that causes alteration of the structure of the foot pad losing its compressibility and function. The diagnosis of heel fat pad syndrome is made by ultrasound study. Treatment is primarily based on conservative measures. Infiltration with platelet-rich plasma is proposed as a therapeutic option with the aim of improving pain and inflammation of the plantar fat pad. We report the first published case of ultrasound-guided infiltration with platelet-rich plasma as a treatment for heel fat pad syndrome.

Association of Calcaneal Bone Marrow Lesions and Plantar Fascia Imaging Biomarkers With Chronic Plantar Heel Pain: A Case-Control Study.

OBJECTIVE: To determine associations between chronic plantar heel pain (CPHP) and imaging biomarkers derived from magnetic resonance imaging (MRI) and ultrasonography. METHODS: We compared 218 participants with CPHP with 100 age- and sex-matched population controls. We assessed imaging biomarkers on MRI (calcaneal bone marrow lesions [BMLs], plantar fascia [PF] signal and thickness, spurs, and fat pad signal) and B-mode/power Doppler ultrasound (PF thickness, echogenicity, and vascularity). Covariate data collected included demographic characteristics, disease history, clinical measures, and physical activity by accelerometry. Data were analyzed using multivariable conditional logistic regression. RESULTS: Plantar calcaneal BML size (mm2 , odds ratio [OR] 1.03 [95% confidence interval (95% CI) 1.02-1.05]), larger plantar spurs (OR for spurs >5 mm 2.15 [95% CI 1.13-4.10]), PF signal (OR for signal penetrating >50% of the dorsoplantar width 12.12 [95% CI 5.36-27.42]), PF thickness (mm, OR for MRI 3.23 [95% CI 2.36-4.43] and ultrasound OR 3.78 [95% CI 2.69-5.32]), and echogenicity (diffusely hypoechoic OR 7.89 [95% CI 4.02-15.48] and focally hypoechoic OR 24.92 [95% CI 9.60-64.69]) were independently associated with CPHP. PF vascularity was uncommon, occurring exclusively in cases (cases with signal n = 47 [22%]). Combining imaging biomarkers into 1 model, plantar BMLs and PF imaging biomarkers, but not fat pad signal or heel spurs, were independently associated with CPHP. CONCLUSION: Calcaneal BMLs and PF imaging biomarkers are associated with CPHP. Further research is required to understand whether these different markers represent distinct phenotypes of heel pain, and if so, whether there are specific treatment implications.

Ultrasonography of heel entheses in axial spondyloarthritis patients: frequency and assessment of associated factors.

PURPOSE: Foot entheses involvement is a common manifestation of spondyloarthritis. The superiority of ultrasonography examination in foot entheses damages detection has been reported. We aimed to compare the ultrasonography findings of foot entheses between spondyloarthritis patients. and healthy controls and to identify factors associated with enthesitic heel involvement. METHODS: We conducted a cross-sectional study including 37 patients with axial spondyloarthritis (G1) and 37 healthy subjects matched by age and gender (G0). The following pro-inflammatory cytokines were measured: Interleukin (IL-)1, IL-6, IL-17, and IL-23. A blind ultrasonography of foot entheses was performed to examine calcaneal tendon (CT) and plantar fascia (PF). RESULTS: The mean age was 44.62 ± 12.31 years. Non-steroidal anti-inflammatory drugs were taken in 92% of patients. Clinical heel enthesopathy was noted in 10 patients (27%) of G1. No participant has enthesitic pain in G0. Ultrasonography changes in CT and PF were more frequent in G1 than G0 (p = 0.001 and p = 10-3, respectively). In the PF, tendon thickening was significantly higher in G1 than G0 (p = 0.03). Power Doppler in both enthesitic sites was exclusively observed in G1 (p = 10-3). Regarding associated factors, CT enthesophytes were less frequent in patients taking non-steroidal anti-inflammatory drugs continuously or having regular physical activity. PF structural damages were associated with higher erythrocyte sedimentation rate (p = 0.02), higher IL-23 level (p = 0.01), and higher disease activity (p = 0.04). CONCLUSION: Ultrasonography lesions of heel entheses were frequent in spondyloarthritis. Disease activity and inflammatory markers were higher in patients with heel enthesitis. Non-steroidal anti-inflammatory drugs intake and regular physical activity may prevent enthesophytes' occurrence.

Ultrasonic evaluation of plantar fascia in patients with osteoarthritis of the knee.

To study the changes of plantar fascia in patients with knee osteoarthritis. Collect knee arthritis surgery patients and according to the length of the course is divided into long-course and short-course group, collection of healthy volunteers as control group at the same time, basic information such as age, height, weight, and body mass index (BMI) were recorded; the application of Philips and Siemens ultrasonic diagnostic instrument, a foot plantar fascia in patients with knee osteoarthritis in ultrasonic scanning, measuring the thickness of the heel of plantar fascia, observe its sonographic manifestation; age, BMI, and plantar fascia thickness were compared between groups. The plantar fascia thickness of the normal control group was 0.30 ±â€…0.06 cm on the left side and 0.30 ±â€…0.05 cm on the right side. The plantar fascia thickness of the long-course group was 0.44 ±â€…0.10 cm on the left side and 0.42 ±â€…0.10 cm on the right side. The plantar fascia thickness of the group with short course of disease was 0.37 ±â€…0.06 cm on the left side and 0.34 ±â€…0.7 cm on the right side. Multivariable analysis of variance was used to compare the thickness of plantar fascia in the long-course group, the short-course group, and the control group, P < .05; there were statistical differences among the 3 groups. Multivariate analysis of variance was used to compare the general data of the long-course group, the short-course group, and the control group. Age: the long-course group was compared with the short-course group and the control group, P < .05; short-course group compared with control group, P > .05. BMI: compared with long-course group and short-course group, P < .05; long course of disease group compared with short course of disease group, P > .05. BMI was statistically different between the case group and the control group. Plantar fascia was thickened in patients with knee osteoarthritis, and the thickening of plantar fascia was related to BMI. The thickening of plantar fascia was uneven, and the degree of thickening was related to the course of disease. At the same time, the sonogram of plantar fascia was less echogenic than that of normal controls.

The relationship between ultrasonography with or without contrast and the clinical outcome in plantar fasciitis.

BACKGROUND: Plantar fasciitis (PF) is a common disorder without objective parameters for disease severity. PURPOSE: To investigate whether structural changes in the plantar fascia and heel fat pad determined by ultrasound scanning with or without contrast are related to outcome measures in patients with symptomatic PF and to investigate whether there is an association between changes in US findings and improvement in pain and function. METHODS: All patients (n = 90) in a randomized controlled trial treated with training and/or glucocorticosteroid injection were assessed for morning pain, function pain, Foot Function Index (FFI), and ultrasound measured thickness of the fascia and heel fat pad at entry and after 6 months. Thirty patients were included in a longitudinal study that assessed pain, function, and microvascular volume (MV) by contrast-enhanced ultrasound at entry and after 5 months of treatment. RESULTS: None of the ultrasound parameters at the initial examination were related to clinical outcomes at 5-6 months. Changes in US measured thickness of the fascia but not the fat pad correlated with improvement in all outcome measures at 6 months (FFI: r = 0.30, p = 0.005, morning pain: r = 0.21, p = 0.046, function pain: r = 0.28, p = 0.007). MV did not change despite significant improvement in symptoms. CONCLUSION: Changes in ultrasound measured fascia thickness are associated with clinical improvement in PF patients.

Ultrasound examination for a heel scar: seeing/treating the painful superficial fascia.

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Magnetic resonance imaging characteristics in patients with spondyloarthritis and clinical diagnosis of heel enthesitis: post hoc analysis from the phase 3 ACHILLES trial.

OBJECTIVE: To investigate the imaging characteristics and clinically assess heel enthesitis in spondyloarthritis (SpA) by applying in a post hoc analysis the Heel Enthesitis Magnetic Resonance Imaging Scoring system (HEMRIS) in blinded and centrally-read MRI data from the ACHILLES trial (NCT02771210). METHODS: ACHILLES included patients (≥18 years) with active psoriatic arthritis or axial SpA with clinical and MRI-positive heel enthesitis refractory to standard treatment. Patients were randomized to receive subcutaneous secukinumab 150/300 mg or placebo. At week 24, patients on placebo were switched to secukinumab treatment. MRI-positive heel enthesitis was confirmed in all patients by local investigators. MRIs were performed at 3 timepoints: screening and weeks 24 and 52. In the present analysis, all MRIs were re-evaluated by 2 blinded central readers in a consensus read fashion for a priori defined MRI parameters based on HEMRIS. RESULTS: At screening, 171/204 (83.8%) of patients presented with entheseal inflammation and/or structural damage, considering both the Achilles tendon and plantar fascia. Pathologies were more evident in the Achilles tendon area compared to the plantar aponeurosis. The most frequent pathologies were intra-tendon hypersignal and retrocalcaneal bursitis. The mean total entheseal inflammation score at screening in the Achilles tendon area was 2.99 (N=204) and the mean change (standard deviation [SD]) from screening to weeks 24 and 52 was - 0.91 (1.99) and - 0.83 (2.12) in the secukinumab group vs - 0.48 (1.86) and - 0.80 (1.98) in the placebo-secukinumab group, respectively. The mean total structural damage score at screening was 1.36 (N=204) and the mean change (SD) from screening to weeks 24 and 52 was 0.00 (0.65) and - 0.06 (0.56) in the secukinumab group vs 0.08 (0.48) and 0.04 (0.75) in the placebo-secukinumab group, respectively. CONCLUSIONS: Based on the newly developed HEMRIS, entheseal inflammation and/or structural damage was confirmed in 83.3% of ACHILLES patients. Pathologies were more evident in the Achilles tendon area compared to plantar fascia, with the inflammatory parameters being more responsive with secukinumab treatment compared to placebo. The present analysis, with detailed information on individual MRI parameters, contributes to the scientific debate on heel enthesitis. TRIAL REGISTRATION: ClinicalTrials.gov NCT02771210 .

Effect of loading history on material properties of human heel pad: an in-vivo pilot investigation during gait.

BACKGROUND: This study was aimed to develop a novel dynamic measurement technique for testing the material properties and investigating the effect of continuous compression load on the structural and mechanical properties of human heel pad during actual gait. METHODS: The dual fluoroscopic imaging system (DFIS) and dynamic foot-ground contact pressure-test plate were used for measuring the material properties, including primary thickness, peak strain, peak stress, elastic modulus, viscous modulus and energy dissipation rate (EDR), both at time zero and following continuous loading. Ten healthy pilot subjects, aged from 23 to 72 (average: 46.5 ± 17.6), were enrolled. A "three-step gait cycle" is performed for all subjects, with the second step striking at a marked position on the force plate with the heel to maintain the location of the tested foot to be in the view of fluoroscopes. The subjects were measured at both relaxed (time-zero group) and fatigue (continuous-loading group) statuses, and the left and right heels were measured using the identical procedures. RESULTS: The peak strain, peak stress, elastic modulus, and EDR are similar before and after continuous load, while the viscous modulus was significantly decreased (median: 43.9 vs. 20.37 kPa•s; p < 0.001) as well as primary thicknesses (median: 15.99 vs. 15.72 mm; p < 0.001). Age is demonstrated to be moderately correlated with the primary thicknesses both at time zero (R = -0.507) and following continuous load (R = -0.607). The peak stress was significantly correlated with the elastic modulus before (R = 0.741) and after continuous load (R = 0.802). The peak strain was correlated with the elastic modulus before (R = -0.765) and after continuous load (R = -0.801). The correlations between the viscous modulus and peak stress/ peak strain are similar to above(R = 0.643, 0.577, - 0.586 and - 0.717 respectively). The viscous modulus is positively correlated with the elastic modulus before (R = 0.821) and after continuous load (R = 0.784). CONCLUSIONS: By using dynamic fluoroscopy combined with the plantar pressure plate, the in vivo viscoelastic properties and other data of the heel pad in the actual gait can be obtained. Age was negatively correlated with the primary thickness of heel pad and peak strain, and was positively correlated with viscous modulus. Repetitive loading could decrease the primary thickness of heel pad and viscous modulus.

A quantitative comparison of plantar soft tissue strainability distribution and homogeneity between ulcerated and non-ulcerated patients using ultrasound strain elastography.

The primary objective of this study was to develop a method that allows accurate quantification of plantar soft tissue stiffness distribution and homogeneity. The secondary aim of this study was to investigate if the differences in soft tissue stiffness distribution and homogeneity can be detected between ulcerated and non-ulcerated foot. Novel measures of individual pixel stiffness, named as quantitative strainability (QS) and relative strainability (RS) were developed. Strain Elastography data obtained from 39 (nine with active diabetic foot ulcers) patients with diabetic neuropathy. The patients with active diabetic foot ulcer had wound in parts of the foot other than the first metatarsal head and the heel where the elastography measures were conducted. RS was used to measure changes and gradients in the stiffness distribution of plantar soft tissues in participants with and without active diabetic foot ulcer. The plantar soft tissue homogeneity in superior-inferior direction in the left forefoot was found to be significantly (p < 0.05) higher in ulcerated group compared to non-ulcerated group. The assessment of homogeneity showed potentials to further explain the nature of the change in tissue that can increase internal stress. This can have implications in assessing the vulnerability to plantar soft tissue damage and ulceration in diabetes.

Medical imaging for plantar heel pain: a systematic review and meta-analysis.

BACKGROUND: Medical imaging can be used to assist with the diagnosis of plantar heel pain. The aim of this study was to synthesise medical imaging features associated with plantar heel pain. METHODS: This systematic review and meta-analysis conducted searches in MEDLINE, CINAHL, SPORTDiscus, Embase and the Cochrane Library from inception to 12th February 2021. Peer-reviewed articles of cross-sectional observational studies written in English that compared medical imaging findings in adult participants with plantar heel pain to control participants without plantar heel pain were included. Study quality and risk of bias was assessed using the National Institutes of Health quality assessment tool for observational cohort and cross-sectional studies. Sensitivity analyses were conducted where appropriate to account for studies that used unblinded assessors. RESULTS: Forty-two studies (2928 participants) were identified and included in analyses. Only 21% of studies were rated 'good' on quality assessment. Imaging features associated with plantar heel pain included a thickened plantar fascia (on ultrasound and MRI), abnormalities of the plantar fascia (on ultrasound and MRI), abnormalities of adjacent tissue such as a thickened loaded plantar heel fat pad (on ultrasound), and a plantar calcaneal spur (on x-ray). In addition, there is some evidence from more than one study that there is increased hyperaemia within the fascia (on power Doppler ultrasound) and abnormalities of bone in the calcaneus (increased uptake on technetium-99 m bone scan and bone marrow oedema on MRI). CONCLUSIONS: People with plantar heel pain are more likely to have a thickened plantar fascia, abnormal plantar fascia tissue, a thicker loaded plantar heel fat pad, and a plantar calcaneal spur. In addition, there is some evidence of hyperaemia within the plantar fascia and abnormalities of the calcaneus. Whilst these medical imaging features may aid with diagnosis, additional high-quality studies investigating medical imaging findings for some of these imaging features would be worthwhile to improve the precision of these findings and determine their clinical relevance.

Plantar Soft Tissue Characterization Using Reverberant Shear Wave Elastography: A Proof-of-Concept Study.

Plantar soft tissue stiffness provides relevant information on biomechanical characteristics of the foot. Therefore, appropriate monitoring of foot elasticity could be useful for diagnosis, treatment or health care of people with complex pathologies such as a diabetic foot. In this work, the reliability of reverberant shear wave elastography (RSWE) applied to plantar soft tissue was investigated. Shear wave speed (SWS) measurements were estimated at the plantar soft tissue at the first metatarsal head, the third metatarsal head and the heel from both feet in five healthy volunteers. Experiments were repeated for a test-retest analysis with and without the use of gel pad using a mechanical excitation frequency range between 400 and 600 Hz. Statistical analysis was performed to evaluate the reliability of the SWS estimations. In addition, the results were compared against those obtained with a commercially available shear wave-based elastography technique, supersonic imaging (SSI). The results indicate a low coefficient of variation for test-retest experiments with gel pad (median: 5.59%) and without gel pad (median: 5.83%). Additionally, the values of the SWS measurements increase at higher frequencies (median values: 2.11 m/s at 400 Hz, 2.16 m/s at 450 Hz, 2.24 m/s at 500 Hz, 2.21 m/s at 550 Hz and 2.31 m/s at 600 Hz), consistent with previous reports at lower frequencies. The SWSs at the plantar soft tissue at the first metatarsal head, third metatarsal head and heel were found be significantly (p<0.05) different, with median values of 2.42, 2.16 and 2.03 m/s, respectively which indicates the ability of the method to differentiate between shear wave speeds at different anatomical locations. The results indicated better elastographic signal-to-noise ratios with RSWE compared to SSI because of the artifacts presented in the SWS generation. These preliminary results indicate that the RSWE approach can be used to estimate the plantar soft tissue elasticity, which may have great potential to better evaluate changes in biomechanical characteristics of the foot.

The Zadek calcaneal osteotomy in Haglund's syndrome of the heel: Clinical results and a radiographic analysis to explain its efficacy.

Local debridement or decompression of the posterior heel in Haglund's syndrome yields variable results. This condition is sometimes due to an excessively long calcaneus rather than simply a large posterosuperior bony prominence. Failure to address this abnormality may explain the poor results in some series. We recently published a new measurement (the X/Y ratio) which, combined with the calcaneal pitch angle, assesses the abnormality of the shape of the calcaneus. The Zadek osteotomy strongly modifies that shape. We retrospectively reviewed 50 patients treated by a Zadek osteotomy at a mean 7 years follow-up using the AOFAS ankle-hindfoot score, the VISA-A score and Tegner scale. We measured only the X/Y ratio and the calcaneal inclination angle, as the classically described radiographic measurements in Haglund's syndrome are unreliable. We then assessed the condition of the distal end of the Achilles tendon with an MRI. Our results demonstrate excellent outcomes(40/50, 80%) following Zadek osteotomy and correspond to the change in pre- and post-operative measurements, especially the X/Y ratio. An algorithm using those geometrical measurements of the calcaneus is proposed for decision making in Haglund's syndrome. Level of clinical evidence: Level 3.

Ultrasonic Evaluation of the Heel Fat Pad under Weight-Bearing Conditions Using a Polymethylpentene Resin Plate: Part 1.

To evaluate the two-layer structure of the heel fat pad (HFP) from non-weight-bearing to full-weight-bearing conditions, we developed an instrument that assesses these changes from the sole through a polymethylpentene resin plate (PMP) with ultrasonography. For actual use, we investigated the influence on measured values and ultrasonogram appearance by interposing the PMP. Additionally, as the PMP may be bent under weight-bearing conditions, its influence on the measured values was investigated. First, two examiners measured the distances inside the phantom with and without a PMP. Second, ultrasonograms were obtained from 40 healthy adults with and without a PMP, and the thicknesses of the whole layer and the two layers of the HFP were measured using the same ultrasonogram. For each experiment, reproducibility was investigated. Third, the distances inside the phantom were measured and compared through the bent PMP, which models the weight-bearing condition, and the flat PMP. The reproducibility of the measurements was equivalent with and without the PMP interposed. Potential bias in measured values arising from deformation of PMP under weight-bearing conditions was not detected. Overall, the PMP's interposition and the bending of the PMP might not influence the measured values and reproducibility of the measurements.